British Rail Class 377

The trains work suburban services in South London, and main-line commuter services to Sussex, Surrey, Kent and the South Coast, on which they replaced 4Cig and 4Vep slam-door stock that was more than 40 years old and did not meet modern health and safety requirements. Built in the early 2000s, the units had a troubled introduction: being fully air-conditioned, their higher power consumption compared to the trains they replaced led to major upgrades being required to the 750 V DC third-rail power supply used in the former Southern region.{{cite magazine |url=http://dspace.dial.pipex.com/town/square/ca14/ALYCIDON%20RAIL/INFORMED%20SOURCES%20ARCHIVE/INF%20SRCS%202003/Informed%20Sources%2005%202003%20p4.htm |archive-url= https://web.archive.org/web/20110604025430/http://dspace.dial.pipex.com/town/square/ca14/ALYCIDON%20RAIL/INFORMED%20SOURCES%20ARCHIVE/INF%20SRCS%202003/Informed%20Sources%2005%202003%20p4.htm |url-status= dead |archive-date= 4 June 2011 |author-link= Roger Ford (journalist) |last=Ford |first=Roger |title=SR power upgrade agreements signed |magazine=Modern Railways |date=May 2003 |location=London|via= dspace.dial.pipex.com}} The collapse of Railtrack following the Hatfield accident further delayed this upgrade work, and the new stock did not enter squadron service until 2003.

Class 377s are fitted with external CCTV. There is an open area for wheelchairs, prams and cycles, and both intermediate coaches have toilets. Bodyside power doors are electrically operated, a move away from the air-powered systems of previous generation EMUs. Dual-voltage units are fitted with a Brecknell Willis high-speed pantograph, incorporating a pair of aerofoils on the pan knuckle to steady the pan head against the OLE contact wire.First Capital Connect: Class 377 Drivers' Guide p.91 "The pantograph" 2009.

The configuration of a 5-car Class 377 unit is:

• DMOC(A) – 2 motors on inner bogie, sander, auxiliary converter module
• MOSL – 2 motors on inner bogie, standard toilet (not found on 377/3s)
• PTSOL – pantograph, transformer, compressor, universal-access toilet
• MOS – 2 motors on inner bogie, standard-class interior (only found on Class 377/6 and 377/7 units)
• DMOS(B) – 2 motors on inner bogie, sander, auxiliary converter module

In the 4-car units the driving cars are composite. The first-class saloon is between the driving cab and the first set of passenger doors. 4-car units also do not contain the MOS coach.{{citation needed|date=January 2017}}

The Class 377 use Dellner instead of Tightlock couplings originally used on the Class 375s.{{cite web |url= http://www.railway-technology.com/contractors/brakes/dellner/ |title=Dellner Couplers AB — Automatic and Semi-Permanent Couplers |access-date=10 October 2014}} Southern's 375s were all reclassified to Class 377/3s upon conversion. These reclassified units can still be identified by their 3-car formation. Note that Southeastern's 375s (sub-classes 375/3, 375/6, and 375/7) were also later converted from Tightlock to Dellner couplers but were not reclassified. Its sub-class 375/8 and 375/9 units were fitted with Dellner couplers, as built.{{cite web |url= http://www.southernelectric.org.uk/features/historical-features/index.html |publisher= Southern Electric Group |date=21 April 2006 |title=Southern Electric Fleet Review Summer 2004 |url-status=dead |archive-url= https://web.archive.org/web/20130223073203/http://www.southernelectric.org.uk/features/historical-features/index.html |archive-date=23 February 2013 }}

All units can receive power via third-rail pick-up which provides 750 V DC. There are eight pick-up shoes per unit (twice the number of previous generation 4-car electric multiple units), and this enables them to ride smoothly over most third-rail gaps. The units in the 377/2, 377/5 and 377/7 sub-classes are dual-voltage, and are fitted with a pantograph to pick up 25 kV AC from overhead lines. On these units (and on single-voltage sub-class 377/6), the shoe mechanism is air-operated so that when powered down, or working on AC overhead lines, the shoe is raised out of the way. This is used on trains from Hemel Hempstead to Clapham Junction, which use part of the West Coast Main Line between Hemel Hempstead and Willesden Junction, and then the West London Line towards Clapham Junction. These trains change to third-rail DC supply on a dual-voltage section of the West London line north of Shepherd's Bush.Jacobs, G. (ed) (2008). Railway Track Diagrams 5: Southern and TfL (3rd edition). Bradford-on-Avon: Quail. p. 1R. Since March 2009, dual-voltage Class 377 units operated some Thameslink Bedford to Brighton, Rochester and Ashford services (see below). The Bedford to Brighton services are now run by Class 700s, while the Class 377/5s themselves are now operated by Southeastern.

Among the remaining units, the trailer coach in each unit has a recess in its roof where a pantograph could be fitted, to allow for future conversion to overhead AC power.{{citation needed|date=January 2017}}

In April 2007, as part of the Route Utilisation Strategy for the Brighton Main Line, it was announced that Southern would procure an additional 48 Class 377 carriages to replace an identical number of {{brc|319}} carriages (12 x 4-car units) due to be transferred to First Capital Connect.{{cite web |date=4 April 2007 |url= http://www.dft.gov.uk/pgr/rail/passenger/franchises/moretrains |title=More trains arriving on busy rail routes |publisher=Department for Transport |archive-url=https://web.archive.org/web/20070705181007/http://www.dft.gov.uk/pgr/rail/passenger/franchises/moretrains |archive-date=5 July 2007}} Eleven further dual-voltage units were then added to the order, making a total of 23. The units were commissioned at Southern's Selhurst depot in Croydon before being transferred to First Capital Connect's Bedford Cauldwell depot. The first of these, unit 377501, was delivered to Cauldwell depot on 27 February 2009 after making its first appearance through the Thameslink Central London core. The 377/5s operated mainly on Bedford to Brighton services but in the peaks formed part of First Capital Connect's and Southeastern's joint service to places such as Rochester and Ashford.

Delays in the construction of the Class 377/5s for First Capital Connect saw the temporary transfer of eight of Southern's Class 377/2s to FCC to enable it to implement the planned timetable changes on 22 March 2009. The loss of these units until September 2009 was covered by the temporary cascade of a number of Class 350/1s to Southern from London Midland, which operated services between East Croydon and Milton Keynes.{{cite magazine|title=350s with Southern until November|magazine=Today's Railways UK|issue=95|date=November 2009|page=65}}

In September 2011, it was announced that Southern had begun the procurement of 130 vehicles, due to delays in the procurement of new Thameslink rolling stock that would prevent transfer of the 377/5s in time for the December 2013 timetable change.{{cite magazine |title=Battle of awarding of Thameslink contract to Siemens continues unabated as Southern potentially throws a lifeline to Bombardier's Derby works |url=http://railwayherald.co.uk/magazine/pdf/RHUK/Issue284.pdf |url-status= dead |magazine= Railway Herald |location= Scunthorpe |publication-date=19 September 2011 |issue=283 |page=3 |issn=1751-8091 |archive-url= https://web.archive.org/web/20120509211814/http://railwayherald.com/magazine/download/284 |archive-date=9 May 2012 |access-date=30 October 2022}} The contract was awarded to Bombardier in December 2011.{{cite news |url=http://www.railnews.co.uk/news/general/2011/12/28-boost-for-derby-as-bombardier.html |title= Boost for Derby as Bombardier wins Southern order |work=Railnews |date=28 December 2011 |access-date=9 January 2012}}{{cite news |url= http://www.railnews.co.uk/news/2012/11/16-dft-acts-to-ease-thameslink.html |title=DfT acts to ease Thameslink trains logjam |work=Railnews |date=16 November 2012 |access-date=16 November 2012}} The additional eight five-car units (from an option in the contract for 40 additional vehicles) are dual-voltage and known as Class 377/7.{{cite magazine |magazine=Today's Railways UK|date=March 2013|issue=135|page=31}}{{title needed |date=March 2025}}

In December 2011, three Class 377/2 units were transferred from Southern to First Capital Connect to allow more 12-car services to operate.{{cite magazine|title=First Capital Connect runs first 12 car Thameslink train|magazine=Rail Magazine|issue=686 29|date=December 2011|page=14}}

During mid-2013, the first of the new Class 377/6s arrived from Derby for type testing, and since October 2013, these units have been used in passenger service, initially in peak-hour services on the Sutton and Mole Valley lines, Epsom Downs Branch, Tattenham Corner Line and the Caterham Line.{{citation needed|date=January 2017}}

Southeastern received 25 Class 377 units (the 23 Class 377/5s and 2 Class 377/1s) in recent years,{{when|date=January 2022}} as specified in Department for Transport documents, published in September 2013, relating to the new combined Thameslink, Southern and Great Northern Franchise.{{cite web |url= https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/245041/invitation-to-tender.pdf |title=Thameslink, Southern and Great Northern Franchise: Invitation to Tender |publisher=Department for Transport |location=London |date=September 2013 |page=75 |access-date=9 October 2013}}

Porterbrook is funding the £55 million five-year Project Aurora programme to refurbish 214 Class 377 Electrostars operated on Southern services.{{cite magazine |url= https://www.railwaygazette.com/uk/gtr-launches-55m-electrostar-refurbishment/57369.article |title=GTR launches £55m Electrostar refurbishment |magazine= Railway Gazette International|date=16 September 2020 |access-date=10 February 2021}} The work started in 2020 and is being done at Selhurst depot. 377 430 was the first unit to be completed in early 2021.{{cite magazine |url= https://www.railwaygazette.com/uk/southerns-first-refurbished-electrostar-returns-to-service/58470.article |title=Southern's first refurbished Electrostar returns to service |magazine= Railway Gazette International |date=9 February 2021 |access-date=10 February 2021}} Changes include the installation of screens showing live GTR and London Underground service information, the provision of USB and power points, energy-saving LED lighting and a passenger-counting system which will enable GTR to analyse how busy individual services are.{{cite magazine |url= https://www.railwaygazette.com/uk/gtr-launches-55m-electrostar-refurbishment/57369.article |title=GTR launches £55m Electrostar refurbishment |magazine= Railway Gazette International |date=16 September 2020 |access-date=10 February 2021}}

• Mainline and Redhill Routes: London Victoria and London Bridge to Brighton, Reigate, Tonbridge, Eastbourne, Ore, Portsmouth, Southampton, Littlehampton and Bognor Regis
• East Coastway: Brighton to Seaford, Eastbourne, Hastings and Ore
• West Coastway: Brighton to Portsmouth, Littlehampton, Bognor Regis and Southampton
• West London Route: Clapham Junction to Watford Junction
• Oxted Line: London Victoria to East Grinstead
• Outer Suburban services: London Victoria and London Bridge to Tattenham Corner, Epsom, Horsham and Dorking
• Inner Suburban services: London Victoria and London Bridge to Caterham, Sutton, Epsom Downs, West Croydon and Beckenham Junction via Crystal Palace

In December 2016 Southeastern (Govia) received 8 units (377501-377508), transferred from Thameslink. In September 2017 these were joined by an additional 17 units (377509-523 & 377163/164)

Southeastern is also set to receive 13 Class 377/1s (377121-133) from Southern to replace ageing Class 465 units, with 377121 and 377122 in passenger service since 2 January 2025.{{Cite magazine |title=Southeastern to receive 13 Class 377s from Govia Thameslink as part of EMU reshuffle |url=https://www.railmagazine.com/news/fleet/2024/11/28/southeastern-to-receive-13-class-377s-from-govia-thameslink-as-part-of-emu-reshuffle |access-date=29 November 2024 |magazine=Rail Magazine}}

In 2016, 19 of the 23 Class 377/5 units were planned to be transferred to Great Northern, for use on non-stop London-Cambridge services. However, the 29 former Thameslink Class 387/1s were transferred, instead.{{cite magazine|title=Trio of GTR Class 387/1s readied for move to Great Northern duties |magazine=Rail Magazine|issue=|date=|page= }} The Class 377/5s were later transferred to Southeastern, as part of their requirement for additional capacity.

{{Wide image|Southern Class 377-1-4.png|x60px|Illustration of a Southern Class 377/1/4 unit}}

{{Wide image|Southern Class 377-2-5.png|x60px|Illustration of a Southern Class 377/2 unit}}

{{Wide image|Southern Class 377-3.png|x60px|Illustration of a Southern Class 377/3 unit}}

{{Wide image|Southeastern Class 377-5.png|x60px|Illustration of a Southeastern Class 377/5 unit}}

{{Wide image|Southern Class 377-6.png|x60px|Illustration of a Southern Class 377/6 unit}}

{{Wide image|Southern Class 377-7.png|x60px|Illustration of a Southern Class 377/7 unit}}

File:377 317 derailed at Tonbridge 230820.JPG

On 28 November 2016, a fire broke out in the MOSL car of a Southern Class 377 (unit 377442) at Eastbourne station, causing damage to the ceiling and interior. The cause was later identified to be faulty wiring within a hand dryer located in the toilet.{{Cite news |url=http://www.eastbourneherald.co.uk/news/hand-dryer-caused-eastbourne-train-fire-1-7709270 |title=Hand dryer caused Eastbourne train fire |work=Eastbourne Herald |date= 2 December 2016|access-date=20 September 2018}}

On 17 February 2018, a 377 (unit 377454) hit a car on a level crossing at Barns Green near {{rws|Horsham}}. The two occupants of the car died at the scene.{{Cite news |url=https://www.bbc.co.uk/news/uk-england-sussex-43097342 |title=Barns Green: Boy and granddad die as train hits car |work=BBC News |date=17 February 2018 |access-date=20 September 2018}}

On 8 May 2019, 377142 collided with the buffer stop at London Victoria station.{{cite web |last=Clifton |first=Katy |date=8 May 2019 |title=Victoria station crash: Southern Rail train 'hits buffers causing loud bang and smoke' in front of shocked commuters |url=https://www.standard.co.uk/news/london/victoria-station-crash-southern-rail-train-crashes-into-buffers-causing-loud-bang-and-smoke-in-front-a4137476.html |access-date=8 May 2019 |publisher=Evening Standard}}

On 23 August 2020, 377317 was derailed at the exit of the Tonbridge Jubilee Sidings.{{cite tweet |author=Network Rail |author-link=Network Rail |user=NetworkRailSE |number=1297777601755459584 |date=24 August 2020 |title=Due to Sunday's low-speed derailment of an empty train in the depot near Tonbridge Station our engineers are continuing to work to re-rail the train and check the signalling and track systems in the area. |access-date=24 August 2020 }}

{{Reflist}}

• {{cite magazine|title=Hundred up for Southern's Class 377 refresh|magazine=The Railway Magazine|pages=80|issue=1345|volume=159|date=May 2013|location=Horncastle|publisher=Mortons Media Group|issn=0033-8923|oclc=750645684}}

• {{commons category-inline|British Rail Class 377}}

{{Bombardier Turbostar, Electrostar and Alstom Aventra families}}

{{British Rail EMU}}

Category:Bombardier Transportation multiple units

377

Category:Train-related introductions in 2003

Category:750 V DC multiple units

Category:25 kV AC multiple units